Why forefoot striking in minimal shoes might positively change the course of running injuries

It is believed that human ancestors evolved the ability to run bipedally approximately 2 million years ago. This form of locomotion may have been important to our survival and likely has influenced the evolution of our body form. As our bodies have adapted to run, it seems unusual that up to 79% of modern day runners are injured annually. The etiology of these injuries is clearly multifactorial. However, 1 aspect of running that has significantly changed over the past 50 years is the footwear we use. Modern running shoes have become increasingly cushioned and supportive, and have changed the way we run. In particular, they have altered our footstrike pattern from a predominantly forefoot strike(FFS) landing to a predominantly rearfoot strike(RFS) landing. This change alters the way in which the body is loaded and may be contributing to the high rate of injuries runners experience while engaged in an activity for which they were adapted. In this paper, we will examine the benefits of barefoot running(typically an FFS pattern),and compare the lower extremity mechanics between FFS and RFS. The implications of these mechanical differences, in terms of injury, will be discussed. We will then provide evidence to support our contention that FFS provides an optimal mechanical environment for specific foot and ankle structures, such as the heel pad, the plantar fascia, and the Achilles tendon. The importance of footwear will then be addressed, highlighting its interaction with strike pattern on mechanics. This analysis will underscore why footwear matters when assessing mechanics. Finally, proper preparation and safe transition to an FFS pattern in minimal shoes will be emphasized. Through the discussion of the current literature, we will develop a justification for returning to running in the way for which we were adapted to reduce running-related injuries.

The Black Protests in Poland: An Example of an Anti-pastoral Revolution

Michel Foucault in Security, Territory, Population: Lectures at the Collège de France, 1977-1978 argues, that there has never been such a thing as an anti-pastoral revolution in Western societies. Yes, we have had revolutions against the disciplinary apparatus and legal devices of power (schools, hospitals, prisons) and we have had examples of revolutions against the economic foundations of social inequality, but there has never been a genuine revolution against pastoral power as a power relating to the conduct of individuals (but also entire social groups) and their disposition to “voluntary submission” to the will of external authorities. In my paper, I would like to reflect on this thesis, and taking it quite seriously, to look for examples of such revolutions. One of them is a women’s strike in Poland during the power of the conservative government of “Law and Justice”. Mainly referring to the texts of Silvia Federici and Paul Preciado, I will want to reflect on contemporary practices of reclaiming the body in contemporary capitalism. I will defend the thesis that regaining control over sexuality and reproduction means changing the material conditions of life and modern reproductive technologies.

The deterministic condition for the ground reaction force acting point on the combined knee valgus and tibial internal rotation moments in early phase of cutting maneuvers in female athletes

Background:Combined knee valgus and tibial internal rotation(VL+IR)moments have been shown to stress the anterior cruciate ligament(ACL)in several in vitro cadaveric studies.To utilize this knowledge for non-contact ACL injury prevention in sports,it is necessary to elucidate how the ground reaction force(GRF)acting point(center of pressure(CoP))in the stance foot produces combined knee VL+IR moments in risky maneuvers,such as cuttings.However,the effects of the GRF acting point on the development of the combined knee VL+IR moment in cutting are still unknown.Methods:We first established the deterministic mechanical condition that the CoP position relative to the tibial rotational axis differentiates the GRF vector’s directional probability for developing the combined knee VL+IR moment,and theoretically predicted that when the CoP is posterior to the tibial rotational axis,the GRF vector is more likely to produce the combined knee VL+IR moment than when the CoP is anterior to the tibial rotational axis.Then,we tested a stochastic aspect of our theory in a lab-controlled in vivo experiment.Fourteen females performed 60˚cutting under forefoot/rearfoot strike conditions(10 trials each).The positions of lower limb markers and GRF data were measured,and the knee moment due to GRF vector was calculated.The trials were divided into anterior-and posterior-CoP groups depending on the CoP position relative to the tibial rotational axis at each 10 ms interval from 0 to 100 ms after foot strike,and the occurrence rate of the combined knee VL+IR moment was compared between trial groups.Results:The posterior-CoP group showed significantly higher occurrence rates of the combined knee VL+IR moment(maximum of 82.8%)at every time point than those of the anterior-CoP trials,as theoretically predicted by the deterministic mechanical condition.Conclusion:The rearfoot strikes inducing the posterior CoP should be avoided to reduce the risk of non-contact ACL injury associated with the combined knee VL+IR stress.

Neodymium-doped Yttrium Aluminum Garnet Transparent Laser Ceramics Prepared by Co-precipitation Method

Transparent polycrystaUine neodymiumdoped yttrium aluminum garnet ceramics （Nd：YAG） with better chemical stability, excellent optical and high temperature mechanical property is becoming a new laser host material. The Nd：YAG precursor powders with loosely dispersed, slightly agglomerated and YAG cubic crystal phase were synthesized at 1100 ℃ by the co-precipitation method combined with the reverse strike,

Analysis of the Flow Field and Impact Force in High-Pressure Water Descaling

This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling processes.In particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is examined.Assuming a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are determined.It is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary region.As the target distance increases,the velocity of the water jet in the central region decreases.Through comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.

Evolution of the deformation field and earthquake fracture precursors of strike-slip faults

Seismic hazard analysis is gaining increased attention in the present era because of the catastrophic effects of earthquakes.Scientists always have as a goal to develop new techniques that will help forecast earthquakes before their reoccurrence. In this research,we have performed a shear failure experiment on rock samples with prefabricated cracks to simulate the process of plate movement that forms strike-slip faults. We studied the evolution law of the deformation field to simulate the shear failure experiment, and these results gave us a comprehensive understanding of the elaborate strain distribution law and its formation process with which to identify actual fault zones. We performed uniaxial compression tests on marble slabs with prefabricated double shear cracks to study the distribution and evolution of the deformation field during shear failure. Analysis of the strain field at different loading stages showed that with an increase in the load, the shear strain field initially changed to a disordered-style distribution. Further, the strain field was partially concentrated and finally completely concentrated near the crack and then distributed in the shape of a strip along the crack. We also computed coefficients of variation(CVs) for the physical quantities u, v, and exy, which varied with the load. The CV curves were found to correspond to the different loading stages. We found that at the uniform deformation stage, the CV value was small and changed slowly,whereas at the later nonuniform deformation stage, the CV value increased sharply and changed abruptly. Therefore, the precursor to a rock sample breakdown can be predicted by observing the variation characteristics of CV statistics. The correlation we found between our experimental and theoretical results revealed that our crack evolution and sample deformation results showed good coupling with seismic distribution characteristics near the San Andreas Fault.

Muscle activity and kinematics of forefoot and rearfoot strike runners

Background:Forefoot strike(FFS) and rearfoot strike(RFS) runners differ in their kinematics,force loading rates,and joint loading patterns,but the timing of their muscle activation is less clear.Methods:Forty recreational and highly trained runners ran at four speeds barefoot and shod on a motorized treadmill. "Barefoot" runners wore thin,five-toed socks and shod runners wore neutral running shoes.Subjects were instructed to run comfortably at each speed with no instructions about foot strike patterns.Results:Eleven runners landed with an FFS when barefoot and shod and eleven runners landed with an RFS when barefoot and shod.The 18remaining runners shifted from an FFS when barefoot to an RFS when shod(shifters).Shod shifters ran with a lower stride frequency and greater stride length than all other runners.All FFS runners landed with more plantarflexed ankles and more vertical lower legs at the beginning of stance compared to RFS runners.FFS runners activated their plantarflexor muscles 1 1%earlier and 10%longer than RFS runners.Conclusion:This earlier and longer relative activation of the plantarrlexors likely enhances the capacity for the passive structures of the foot and ankle to store elastic energy,and may also enhance the performance of the active muscle by increasing the storage of elastic strain energy in the cross-bridaes and activated thin.

On Reading Shelleg’s Sonnet England In 1819

1819 was a year of revolution in Europe and it was a year of great upheavalsin English history.The British people were passing through three historical stor-ms——The Industrial Revolution,The American Revolution,The French Revolu-tion. On one hand,the British people were fighting with the bourgeois for theirown existence.They destroyed the machines and went on strikes.On the otherhand,the reactionary authorities cruelly and savagely suppressed the workers mo-vements.The conflict of two classes was extremely intense.In August 1819,about80,000 workers in Manchester city were going out on strike.The reactionary au-thorities brutally suppressed the strike by arm forces.Hundreds of jobless work-ers were killed and wounded.Thus happened the infamous Peterloo Massarce.

DEFINITING AND ITS GEOLOGIC MEANING OF SOUTH-NORTH TREND FAULTED STRUCTURE BELT IN QIANGTANG BASIN, NORTH PART OF TIBET

There were more expounding to north—west (west) trend fault and north\|east trend fault within Qiangtang Basin, North Part of Tibet, in the past literature. With increasing of geophysical exploration data, nearly east\|west trend structure began to be taken note to. Since the year of 1995, by a synthetic study to geophysical and geological data, that south\|north trend faulted structures are well developed. These structures should be paid much more attention to, because they have important theoretical meaning and practical significance.1 Spreading of south\|north faulted structure belt According to different geological and geophysical data, the six larger scale nearly south\|north faulted structure belt could be distinguished within the scope of east longitude 84°～96° and near Qiangtang Basin. The actual location of the six belts are nearly located in the west of the six meridian of east longitude 85°,87°,89°,91°,93°,95° or located near these meridian. The six south\|north faulted structure belts spread in the same interval with near 2° longitude interval. The more clear and much more significance of south\|north trend faulted structure belts are the two S—N trend faulted structure belts of east longitude 87° and 89°. There are S—N trend faulted structure belts in the west of east longitude 83°,81°, or near the longitudes. The structure belts spreading features,manifestation,geological function and its importance, and inter texture and structure are not exactly so same. The structure belts all different degree caused different region of geological structure or gravity field and magnetic field. There is different scale near S—N trend faulted structure belt between the belts.

Studies on the Surface Rupture Zone of 1303 Hongdong Earthquake of M =8 and Paleoearthquakes of Huoshan Fault in Shanxi Province

An earthquake of M=8 occurred in the Linfen Basin of the Shanxi graben system in 1303,producing a surface rupture zone about 45km long.Compiling a geological map at 1:10,000 and studying in detail the rupture zone,its dextral strike-slip displacement is determined to be 4-8.6 m,and normal dip-slip displacement up to 3.5-5 m.In this paper the geochronological evidence for the formation of the surface rupture zone is provided and the Huoshan fault is confirmed to be the seismogenic structure for the M=8 earthquake.Field trenching enables us to identify two paleoseismic events having occurred along the Huoshan fault since the middle Holocene before the M8 earthquake.A recurrence interval of these three events including 1303 Hongdong M 8 earthquake is determined to be up to 1500-2000 years.The result corresponds to the mean recurrence interval calculated from slip rate on the Huoshan fault during Holocene.

Acute effect of foot strike patterns on in vivo tibiotalar and subtalar joint kinematics during barefoot running

Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patterns influence these specific foot and ankle kinematics.However,technical deficiencies in traditional motion capture approaches limit knowledge of in vivo joint kinematics with respect to rearfoot and forefoot strike patterns(RFS and FFS,respectively).This study uses a high-speed dual fluoroscopic imaging system(DFIS)to determine the effects of different foot strike patterns on 3D in vivo tibiotalar and subtalar joints kinematics.Methods:Fifteen healthy male recreational runners underwent foot computed tomography scanning for the construction of 3-dimensional models.A high-speed DFIS(100 Hz)was used to collect 6 degrees of freedom kinematics for participants’tibiotalar and subtalar joints when they adopted RFS and FFS in barefoot condition.Results:Compared with RFS,FFS exhibited greater internal rotation at 0%-20%of the stance phase in the tibiotalar joint.The peak internal rotation angle of the tibiotalar joint under FFS was greater than under RFS(p<0.001,Cohen’s d=0.92).RFS showed more dorsiflexion at 0%-20%of the stance phase in the tibiotalar joint than FFS.RFS also presented a larger anterior translation(p<0.001,Cohen’s d=1.28)in the subtalar joint at i nitial contact than FFS.Conclusion:Running with acute barefoot FFS increases the internal rotation of the tibiotalar joint in the early stance.The use of high-speed DFIS to quantify the movement of the tibiotalar and subtalar joint was critical to revealing the effects of RF S and FFS during running.

Quantitative characterization of irregular microfracture network and its effect on the permeability of porous media

Based on the comprehensive understanding on microfractures and matrix pores in reservoir rocks,numerical algorithms are used to construct fractured porous media and fracture-pore media models.Connectivity coefficient and strike factor are introduced into the models to quantitatively characterize the connectivity and strike of fracture network,respectively.The influences of fracture aperture,fracture strike and fracture connectivity on the permeability of porous media are studied by using multi-relaxation-time lattice Boltzmann model to simulate fluid flow in them.The greater the strike factor and the smaller the tortuosity of the fractured porous media,the greater the permeability of the fractured porous media.The greater the connectivity coefficient of the fracture network is,the greater the permeability of the fracture-pore media is,and the more likely dominant channel effect occurs.The fracture network connectivity has stronger influence on seepage ability of fracture-pore media than fracture aperture and fracture strike.The tortuosity and strike factor of fracture network in fractured porous media are in polynomial relation,while the permeability and fracture network connectivity coefficient of the fracture-pore media meet an exponential relation.

Prediction of application scope of vertical fracture strike based on scattered wave fracture orientation function

Fracture system plays a very important role in the enrichment and accumulation of oil and gas in the reservoirs. Based on scattering wave information, Fracture Orientation Function （FOF） was built, which can be used to predict the fracture orientations. However, this method has only been verified by physical experiments without studies on the application scope. In this study, based on the linear sliding theory, F0F of the scattering wave was applied to the numerical simulation and the application scope was further studied according to fracture flexibility tensor. According to the fractures filled with gas and liquid, numerical simulation was conducted on the models with various fracture flexibilities. Numerical simulation results were used to inverse fracture orientation with the aid of the FOF of the scattering wave. The results show that it is workable to predict the vertical fracture orientation with the F0F of the scattering wave. Application of this method is more effective when the fractures are filled with gas than liquid. Moreover, the application scope can be predicted by the fracture flexibility.

Retraction: Knockdown of Gab1 Inhibits Cellular Proliferation, Migration, and Invasion in Human Oral Squamous Carcinoma Cells

Following the publication,concerns have been raised about a number of figures in this article.The Western Blot data shown in Figs.2a,2b were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes that had already been published.The authors were contacted and invited to comment on the concerns raised and to provide the original,unmodified figures,but did not respond.The Editors-in-Chief therefore no longer have confidence in the integrity of the data in this article and decided to retract this article.

Retraction: KIF18A is a potential prognostic factor and promotes tumor progression in oral tongue squamous cell carcinoma

Following the publication of this paper,a concerned reader alerted the Editors to the similarities between the data presented in this article and data published in prior works by different authors from different research institutions.Specifically,the colony formation data in Fig.4B,the Western Blot data in Fig.4C,and the tumor data in Figs.5A and 5B appear strikingly similar to data previously published.

Technology Research on Lightning Strike Risk Evaluation of a Cable Car

According to structure function and lightning damage of a cable car, a feasible method of lightning strike risk evaluation for a cable car was put forward based on the evaluation model and evaluation method in the standard IEC62305-2. According to the difference between common buildings and cable cars, problems of height non-uniformity of equivalent section caused by inclination of the cable car and diversity of lightning activity regularity caused by the large area were resolved, and expected annual average frequency of lightning strike was calculated using three dimensional graphic approach and regional lightning characteristic analysis. Based on different types of damage process and loss consequences, according to interception effect against lightning invasion of the lightning protection measures and the method of probability selection proposed in the standard, the probability of casu- alty caused by direct lightning strike in a cable car and a waiting area as well as probabilities of casualty caused by failure of electronic information systems were cal- culated.

Three-dimensional impact kinetics with foot-strike manipulations during running

Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional(3 D) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time profiles.Methods: Impact characteristics were assessed by identifying peak loading rates in each direction(medial–lateral(ML), anterior–posterior(AP),vertical, and 3 D resultant) following foot-strike instructions(fore-foot, mid-foot, subtle heel, and obvious heel strike). Kinematic and kinetic data were analyzed among 9 male participants in each foot-strike condition.Results: Loading rate peaks were observed in each direction and foot-strike condition, differing in magnitude by direction(3 D resultant and vertical > AP > ML, p ≤ 0.031) and foot-strike: ML(fore-foot and mid-foot strike > obvious heel strike, p ≤ 0.032), AP(fore-foot and mid-foot strikes > subtle-heel and obvious heel strikes, p ≤ 0.023). In each direction, the first loading rate peak occurred later during heel strike running relative to fore-foot(p ≤ 0.019), with vertical and 3 D resultant impact durations exceeding shear(ML and AP, p ≤ 0.007) in each condition.Conclusion: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3 D resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.

A Short-Range Quantitative Precipitation Forecast Algorithm Using Back-Propagation Neural Network Approach

A back-propagation neural network （BPNN） was used to establish relationships between the shortrange （0-3-h） rainfall and the predictors ranging from extrapolative forecasts of radar reflectivity, satelliteestimated cloud-top temperature, lightning strike rates, and Nested Grid Model （NGM） outputs. Quan- titative precipitation forecasts （QPF） and the probabilities of categorical precipitation were obtained. Results of the BPNN algorithm were compared to the results obtained from the multiple linear regression algorithm for an independent dataset from the 1999 warm season over the continental United States. A sample forecast was made over the southeastern United States. Results showed that the BPNN categorical rainfall forecasts agreed well with Stage Ⅲ observations in terms of the size and shape of the area of rainfall. The BPNN tended to over-forecast the spatial extent of heavier rainfall amounts, but the positioning of the areas with rainfall ≥25.4 mm was still generally accurate. It appeared that the BPNN and linear regression approaches produce forecasts of very similar quality, although in some respects BPNN slightly outperformed the regression.

冈底斯泽当大型钨铜钼矿Re-Os年龄及陆缘走滑转换成矿作用

在前人获取冈底斯成矿带泽当矿田冲木达铜金矿床条带状层矽卡岩型矿石浸染状辉钼矿Re-Os法等时线年龄40.3±5.6Ma的基础上,新获该矿田内另外两组Re-Os法等时线年龄:明则隐伏斑岩型钼矿床中辉钼矿Re-Os法等时线年龄为30.26±0.69Ma;努日层矽卡岩型钨铜钼矿床中与后期石英闪长玢岩体(E3δo)叠加改造成矿有关的斑点状辉钼矿Re-Os法等时线年龄为23.62±0.97Ma。以走滑型陆缘成矿新认识为出发点,总结了冈底斯成矿带陆缘走滑转换成矿作用的类型特征和时空分布:①斑岩型矿床和层矽卡岩矿床是区带内已知中大型铜多金属矿床的主要类型;②早期(68～38Ma)矿床受到"印-亚陆缘"会聚走滑阶段一、二级序左旋走滑转换构造控制,晚期(30～13Ma)矿床受到"印-亚陆缘"离散走滑阶段三、四级序左旋走滑转换构造控制;③斑岩型矿床的矿体形成受控于走滑推闭型转换断裂构造,层矽卡岩型矿床的矿体形成受控于走滑拉分型转换断裂构造;④区域走滑转换成矿构造应力场具逆时针旋转特征,显示68～13Ma间印度大陆相对亚洲大陆朝NEE作斜向对接作用,走滑主应力场被伸展主应力场替代时间以13～8Ma南北向碰撞裂谷的形成-活动为标志。提出"沿边找钼找钨、沿走滑转换构造带找铜金多金属矿,主攻斑岩-层矽卡岩复合型富-大矿"等今后区域找矿方向。